The aim of present study is to assess whether if basal
insulin, glargine, could improve
insulin secretory function of β-cells compared with
glimepiride when
metformin alone was failed. This was an open-label and multi-center study for 52 weeks in Korean patients with uncontrolled
type 2 diabetes by
metformin monotherapy. Subjects were randomized to
glargine or
glimepiride groups (n = 38 vs. 36, respectively). The primary endpoint was to compare changes in
c-peptide via
glucagon test after 48 weeks. Glycemic efficacy and safety endpoints (
glycated hemoglobin (HbA1c), HOMA-B, fasting plasma
glucose (FPG),
lipid profiles, and
hypoglycemic events) were also checked. The mean disease duration of all subjects was 88.2 months. Changes in
C-peptide was no significant different between groups (P = 0.73), even though insulin secretion was not worsened in both groups at the endpoint.
Glargine was not superior to
glimepiride in other β-cell function indexes such as HOMA-B (P = 0.28). HbA1c and FPG reduced significantly in each groups but not different between two groups. Although, severe
hypoglycemia did not occur, symptomatic
hypoglycemia was more frequent in
glimepiride group (P = 0.01).
Insulin glargine was as effective as
glimepiride in controlling
hyperglycemia and maintaining β-cell function in Korean patients with
type 2 diabetes during 48 weeks study period, after failure of
metformin monotherapy.
Hypoglycemic profile was favorable in the
insulin glargine group and less
weight gain was observed in the
glimepiride group. Our results suggest that
glargine and
glimepiride can be considered after failure of
metformin monotherapy.